Sonically vibratory liquid sprayer



March 26, 1968 A. G. BODINE 3,374,953

SONICALLY VIBRATORY LIQUID SPRAYER Filed Aug. 25, 1965 United States Patent 3,374,953 Patented Mar. 26, 1968 fice 3,374,953 SONICALLY VIBRATORY LIQUID SPRAYER Albert G. Bodine, Los Angeles, Calif. (7877 Woodley Ave., Van Nuys, Calif. 91406) Filed Aug. 25, 1965, Ser. No. 482,361 3 Claims. (Cl. 239-102) ABSTRACT OF THE DISCLOSURE An elastic spray member has an axial duct for con ducting liquid therethrough and an axially aligned spray from the nozzle.

This invention relates generally to liquid sprayers, and more particularly to sprayers for converting liquid into a finely divided or atomized spray through application in a unique manner of sonic vibrations. The invention has typical application to orchard sprayers, paint sprayers, fuel injection systems for internal combustion engines, etc. For simple illustrative purposes, the orchard sprayer application will be primarily used herein for illustrative purposes, but without implied limitation thereto.

The invention is based upon the discovery that if a tubular elastic member having an axial liquid duct and an axially aligned spray discharge nozzle or orifice at the end thereof is subjected to resonant frequency elastic vibrations in a lateral standing wave pattern, while liquid to' be sprayed is being supplied to the liquid duct, the liquid is forcibly ejected from the spray nozzle or orifice in a highly atomized state. The preferred form of the invention utilizes a lateral standing wave pattern of a specialized gyratory type, with each point thereon (excepting at the nodes of standing wave) undergoing a closed gyratory path, circular or elliptical, depending upon the cross-section of the tubular member, and without bodily rotation. This gyratory motion is the resultant of, or can be resolved into, two simultaneous rectilinear component vibrations in two directions at right angles to the longitudinal axis of the tubular member, and at right angles to one another, the two component vibrations being in quadrature with one another, i.e. having ninety degrees phase difference. The usually one-wavelength lateral standing wave pattern in the tubular member has end and middle regions which are elastically vibratory at maximized amplitude, and which are called velocity antinodes, and has nearly stationary regions (nodes) at typically quarter-wavelength distances from each end, with vibration amplitude increasing progressively from each node to the adjacent antinodes. In the gyratory form of this lateral standing wave, the vibrating portions of the tubular member bend elastically so as to move around in a circle, but without bodily rotation, i.e. without turning over and over. Each point on the tubular member that is spaced from a node moves so as to describe a closed path, circular, or elliptical, depending upon the crosssection of the member, with the size of the circle (or ellipse) increasing from the node toward the antinode. If the tubular member is of circular section, and the two transverse components are both in quadrature and of equal amplitude, the tube vibrates circularly, while if the two components are of unequal amplitude, the vibration is elliptical. The described gyratory wave action can be established by applying to the tubular member, at an antinode of the standing wave, a rotating radially directed force vector turning at the resonant standing wave frequency of the tubular member. Two simultaneously applied alternating rectilinear force components in quadrature are the equivalent, as shown above.

While the preferred form of the device uses a lateral standing wave pattern of a gyratory nature, one wavelength long, multiples thereof are of course possible. Also, lateral standing wave patterns in a single plane may be used, or may even be of advantage, in some instances.

One advantage of the gyratory-type vibration is that twice as much sonic power can be thereby utilized as in the simpler case of a lateral vibration in a single lateral plane. Another unique advantage of the present invention is that the gyratory-type vibration affords the tubular liquid conducting member and spray nozzle orifice with a multi-motion sonic action which results in maximum atomization of the liquid.

A major object of the invention may at this time be stated to be the provision of a sonically vibratory liquid sprayer capable of delivering a relatively large volume of sprayed liquid in highly atomized form, relying upon the high acceleration that is incident to sonic wave action .in laterally elastically vibratory members.

As regards acceleration, the values attained in lateral sonic standing wave devices are many times that of gravity, and in this manner, very complete atomization can be achieved. Of course, the higher the frequency of sonic vibration, the higher will be the accelerations involved. The illustrated device is capable of embodiment in dimensions operable from frequencies relatively low in the audible sonic spectrum up to order of fifteen to twenty kilocycles per second. In the kilocycle range, the accelerations involved, and the degree of atomization attained, are exceedingly high.

One feature and advantage of a typical preferred illustrative form of the invention is the fact that the sonic sprayer comprises essentially merely an open hole in a tubular member, and is therefore very easily cleaned. This is especially advantageous when dealing with materials which tend to clog up any small orifices, as is common in ordinary spray-type devices.

The sprayer of the invention utilizes, in its preferred form, an orbiting mass oscillator or sonic vibration generator coupled to the elastically tubular liquid fiow member. Examples are given in certain of my prior patents and applications such as Patent No. 2,960,314 and application Ser. Nos. 112,897 and 402,530. The orbiting mass oscillator, in its preferred form as applied to the sprayer of the present invention, involves an inertia ring capable of spinning or whirling about the tubular vibratory member somewhat after the manner of a hoop on a stick. This inertia ring runs or spins on the tubular member at a velocity antinode region of the latter, and thereby, through application of centrifugal force, activates the tubular member into its intended mode of gyratory standing wave vibration. This orbiting mass type oscillator tends to hold its frequency, power factor, phase angle, and output impedance in proper relation to the resonant tubular liquid flow member, even with changing conditions such as variations in fluid flow and other environmental factors which may substantially vary the resonant frequency and the loading impedance of the system. This automatic accommodating feature of the orbiting mass type oscillator is especially beneficial when dealing with outdoor tools such as orchard sprayers, where the ability to maintain the implement in a high state of maintenance is difiicult to attain. Thus, the present device can start out in a fairly well clogged up and sonically dead condition, and the sustained sonic action of the gyratory oscillator will then function under such conditions to unclog and clean the tool and bring it up into a high-Q operating condition. The factor Q, defined hereinafter in more particular, will be understood to denote a condi- 3 tion of highly desirable operation wherein vibration amplitude is high relative to the work being done, so that a high degree of stability and flywheel effect is obtained.

The orbiting mass gyratory oscillator also maintains a good acoustic output impedance during all of the transition phases while the tool conditions itself for its ultimate high-Q operation.

The orbiting mass type oscillator is operable at a fairly high frequency and particularly with high force output, both of which contribute to the attainment of a large acceleration factor at the vibratory portion of the tool which does the work of liquid atomization. This portion of the tool can very well be nothing more than a straight passage in a tubular member which is subjected to a lateral vibration of substantial amplitude, for example, and preferably, in the gyratory manner hereinabove discussed.

Cerain acoustic phenomena disclosed in the foregoing and hereinafter, are, generally speaking, outside the experience of those skilled in the acoustics art. To aid in a full understanding of these phenomena by those skilled in the acoustics art, and by others, the following general discussion, including definition of terms, is deemed to be of importance.

By the expression sonic vibration I mean elastic vibrations, i.e. cyclic elastic deformations, which travel through a medium with a characteristic velocity of prop-agation. If these vibrations travel longitudinally, or create a longitudinal wave pattern in a medium or structure having uniformly distributed constants of elasticity or modulus, and mass, this is sound wave transmission. Regardless of the vibratory frequency of such sound wave transmission, the same mathematical formulae apply, and the science is called sonics. In addition, there can be elastically vibratory systems wherein the essential features of mass appear as a localized influence or parameter, known as a lumped constant, and another such lumped constant can be a localized or concentrated elastically deformable element, affording a local effect referred to variously as elasticity, modulus, modulus of elasticity, stiffness, stiffness modulus, or compliance, which is the reciprocal of the stiffness modulus. Fortunately, these constants, when functioning in an elastically vibratory system such as mine, have cooperating and mutually influencing effects like equivalent factors in alternatingcurrent electrical systems. In fact, in both distributed and lumped constant systems, mass is mathematically equivalent to inductance (a coil); elastic compliance is mathematically equivalent to capacitance (a condensor); and friction or other pure energy dissipation is mathematically equivalent to resistance (a resistor).

Because of these equivalents, my elastic vibratory systems with their mass and stiffness and energy consumption, and their sonic energy transmission properties, can be viewed as equivalent electrical circuits, where the functions can be expressed, considered, changed and quantitatively analyzed by using well proven electrical formulae.

It is important to recognize that the transmission of sonic energy into the interface or work area between two parts to be moved against one another requires the above mentioned elastic vibration phenomena in order to accomplish the benefits of my invention. There have been other proposals involving exclusively simple bodily vibration of some part. However, these latter do not result in the benefits of my sonic or elastically vibratory action.

Since sonic or elastic vibration results in the mass and elastic compliance elements of the system taking on these special properties akin to the parameters of inductance and capacitance in alternating current phenomena, wholly new performances can be made to take place in the mechanical arts. The concept of acoustic impedance becomes of paramount importance in understanding performances. Here impedance is the ratio of cyclic force or pressure acting in the media to resulting cyclic velocity or motion, just like the ratio of voltage to current. In this sonic adaptation impedance is also equal to media density times the speed of propagation of the elastic vibration.

In this invention impedance is important to the accomplishment of desired ends, such as where there is an interface. A sonic vibration transmitted across an interface between two media or two structures can experience some reflection, depending upon differences of impedance. This can cause large relative motion, if desired, at the interface.

Impedance is also important to consider if optimized energization of a system is desired. If the impedances are adjusted to be matched somewhat, energy transmission is made very effective.

Sonic energy at fairly high frequency can have energy effects on molecular or crystalline systems. Also, these fairly high frequencies can result in very high periodic acceleration values, typically of the order of hundreds or thousands of times the acceleration of gravity. This is because mathematically acceleration varies with the square of frequency. Accordingly, by taking advantage of this square function, I can accomplish very high forces with my sonic systems. My sonic systems preferably accomplish such high forces, and high total energy, by using a type of orbiting mass sonic vibration generator taught in my Patent No. 2,960,3 14, which is a simple mechanical device. The use of this type of sonic vibration generator in the sonic system of the present invention affords an especially simple, reliable, and commercially feasible system.

An additional important feature of these sonic circuits is the fact that they can be made very active, so as to handle substantial power, by providing a high Q factor. Here this factor Q is the ratio of energy stored to energy dissipated per cycle. In other words, with a high Q factor, the sonic system can store a high level of sonic energy, to which a constant input and output of energy is respectively added and subtracted. Circuit-wise, this Q factor is numerically the ratio of inductive reactance to resistance. Moreover, a high Q system is dynamically active, giving considerable cyclic motion where such motion is needed.

Certain definitions should now be given:

Impedance, in an elastically vibratory system, is mathematically, the complex quotient of applied alternating force and linear velocity. It is analogous to electrical impedance. The concise mathematical expression for this impedance is where M is vibratory mass, C is elastic compliance (the reciprocal of stiffness, or of modulus of elasticity) and f is the vibration frequency.

Resistance is the real part R of the impedance, and represents energy dissipation, as by friction.

Reactance is the imaginary part of the impedance, and is the difference of mass reactance and compliance reactance.

Mass reactance is the positive imaginary part of the impedance, given by 21rfM. It is analogous to electrical inductive reactance, just as mass is analogous to inductance.

Elastic compliance reactance is the negative imaginary part of impedance, given by l/27rfC. Elastic compliance reactance is analogous to electrical capacitative reactance, just as compliance is analogous to capacitance.

Resonance in the vibratory circuit is obtained at the operating frequency at which the reactance (the algebraic sum of mass and compliance reactances) becomes zero. Vibration amplitude is limited under this condition to resistance alone, and is maximized. The inertia of the mass elements necessary to be vibrated does not under this condition consume any of the driving force.

A valuable feature of my sonic circuit is the provision of enough extra elastic compliance reactance so that the mass or inertia of various necessary bodies in the system does not cause the system to depart so far from resonance that a large portion of the driving force is consumed and wasted in vibrating this mass. For example, a mechanical oscillator or vibration generator of the type normally used in my inventions always has a body, or carrying structure, for containing the cyclic force generating means. This supporting structure, even when minimal, still has mass, or inertia. This inertia could be a force-wasting detriment, acting as a blocking impedance using up part of the periodic force output just to accelerate and decelerate this supporting structure. However, by use of elastically vibratory structure in the system, the effect of this mass, or the mass reactance resulting therefrom, is counteracted at the frequency for resonance; and when a resonant acoustic circuit is thus used, with adequate capacitance (elastic compliance reactance), these blocking impedances are tuned out of existence, at resonance, and the periodic force generating means can thus deliver its full impulse to the work, which is the resistive component of the impedance.

Sometimes it is especially beneficial to couple the sonic oscillator at a low-impedance (high-velocity vibration) region, for optimum power input and then have high impedance (high-force vibration) at the work point. The sonic circuit is then functioning additionally as a transformer, or acoustic lever, to optimize the effectiveness of both the oscillator region and the work delivering region.

For very high-impedance systems having high Q at high frequency, I sometimes prefer that the resonance elastic system be a bar of solid material such as steel. For lower frequency or lower impedance, especially where large amplitude vibration is desired, I use a fluid resonator. One desirable specie of my invention employs, as the source of sonic power, a sonic resonant system comprising an elastic member in combination with an orbiting mass oscillator or vibration generator, as above mentioned. This combination has many unique and desirable features. For example, this orbiting mass oscillator has the ability to adjust its input power and phase to the resonant system so as to accommodate changes in the work load, including changes in either orboth the reactive impedance and the resistive impedance. This is a very desirable feature in that the oscillator hangs on to the load even as the load changes.

It is important to note that this unique advantage of the orbiting mass oscillator accrues from the combination thereof with the acoustic resonant circuit, so as to comprise a complete acoustic system. In other words, the orbiting mass oscillator is matched up to the resonant part of its system, and the combined system is matched up to the acoustic load, or the job to be accomplished. One manifestation of this proper matching is a characteristic whereby the orbiting mass oscillator tends to lock in to the resonant frequency of the resonant part of the system.

The combined system has a unique performance which is exhibited in the form of a greater effectiveness and particularly greater persistence in a sustained sonic action as the work process proceeds or goes through phases and changes of conditions. The orbiting mass oscillator, in this matched-up arrangement, is able to hang on to the load and continue to develop power as the sonic energy absorbing environment changes with the variations in sonic energy absorption by the load. The orbiting mass oscillator automatically changes its phase angle, and therefore its power factor, with these changes in the resistive impedance of the load.

A further important characteristic which tends to make the orbiting mass oscillator hang on to the load and continue the development of effective power, is that it also accommodates for changes in the reactive impedance of the acoustic environment while the work process continues. For example, if the load tends to add either inductance or capacitance to the sonic system, then the orbiting mass oscillator Will accommodate accordingly. Very often this is accommodated by an automatic shift in frequency of operation of the orbiting mass oscillator by virtue of an automatic feedback of torque to the energy source which drives the orbiting mass oscillator. In other words, if the reactive impedance of the load changes this automatically causes a shift in the resonant response of the resonant circuit portion of the complete sonic system.

, This in turn causes a shift in the frequency of the orbiting plained elsewhere in this discussion the kinds of acoustic environment presented to the sonic source by this invention are uniquely accommodated by the combination of the orbiting mass oscillator and the resonant system. As

r. will be noted, this invention involves the application of sonic power which brings forth some special problems unique to this invention, which problems are primarily a matter of delivering effective sonic energy to the particular work process involved in this invention. The work process, as explained elsewhere herein, presents a special combination of resistive and reactive impedances. These circuit values must be properly met in order that the invention be practiced effectively.

Several present illustrative embodimnts of the invention will now be described, reference for this purpose being had to the accompanying drawings, in which:

FIG. 1 is a longitudinal sectional view through a present illustrative embodiment of the invention;

FIG. 1a is a diagrammatic and exaggerated view illustrative of a gyratory standing wave action preferably employed by the invention;

FIG. 2 is a transverse section taken on line 22 of FIG. 1;

FIG. 3 is a perspective view of the tubular sonically vibratory liquid flow member and its driving inertia ring;

FIG. 4 is a front elevational view of the forward end of the gyrationally vibratory liquid flow member.

In the drawings, and with particular reference to the embodiment of FIGS. 14, the reference numeral 10 designates a tubular spraying rod, composed of an elastic material, such as steel, and adapted to undergo resonant elastic vibratory deformation movements in transverse planes. By reason of its resonant vibration function, this member 10 may be termed a. resonator. This member 10 includes a barrel part 11, formed with an axial liquid bore or duct 12 which terminates in an axial spray discharge nozzle portion having a spray discharge orifice 13. Barrel 11 joins a rearward, coaxial, radially enlarged sleeve part 15, which completes the vibratory tubular resonator member 10. A portion of this sleeve part 15, at a distance approximately a quarter of the length of the member 10 from the rearward extremity of the latter, is exteriorly threaded, and threaded thereon is a rearward end wall or flange 18 of a tubular jacket or outer barrel 19 which extends forwardly toward the front or spray discharge end of the barrel 11. An inner barrel or liner 20 is received inside jacket 19, and is threaded to the latter as at 22. The jacket 19 and liner 20 form an air chest for a later described air chamber 43. The liner 20 has an inner end flange 23 which surrounds sleeve 15 just forwardly of jacket flange 18. Flange 23 preferably fits the sleeve 15 with a small clearance, but is sealed to said sleeve by means of O ring seal 24. This clearance and the O-ring 24 accommodate any slight vibratory amplitude in the region of the flange 23. The flange 18, on the other hand, is connected, in the present embodiment, to the sleeve 15 as closely as possible to a nodal region of the standing wave set up in the tubular member 10, as will be more particularly referred to hereinafter. Thereby, vibration transmission from the tubular member 10 to the jacket 19 is minimized.

Liquid to be treated is conveyed to the sprayer from any suitable source of supply v(not shown) which may deliver the liquid under pressure, via a hose 30 coupled to a tubular stem 32 which reaches inside sleeve 15 and threads through a wall 33 extending transversely across the sleeve 15 at the non-vibratory nodal region of the 7 tubular member 10, Le. at a point typically twenty-five percent of the length of member 10 from its rearward end. Stem 32 discharges through said wall 33 into the rearward end of liquid bore 12, in the manner clearly shown in FIG. 1.

The orbital mass vibration generator, in a present preferred form, is designated generally at G, and will next be described. Around the central portion of the tubular member 10 is formed a raceway groove 36 which laterally guides an inertia ring 37, the bottom of the groove 36 constituting a bearing and raceway for the ring 37. The ring 37 will be seen to have an inner diameter somewhat larger than the external diameter of the member 10 measured at the bottom of the groove 36, preferably in subs-tantially the proportions shown in FIG. 1. Also, preferably, the inner surface 38 of the ring 37 is convex or crowned, so as to afford a good rolling engagement with the member 10, with minimized tendency for lateral wob ble. The inertia ring 37 is formed on its external periphery with a plurality of circumferentially spaced notches 40, affording vanes or buckets for impingement of air jets ejected from tangentially oriented air nozzles 42. The inertia ring 37 is thereby driven so as to roll on or whirl about the tubular member 10. The nozzles 42 are fed from an annular air chamber 43, which is supplied with air under pressure via a passageway 44 formed in the portion 45 of a handle member 46. The passage 44 has connected thereto an air supply hose 48, understood to lead from a source of pressurized air (not shown) and the handle member 46 will be seen to join integrally with one side of the jacket 19. The air supply system feeding the hose 48 will be understood to be under a variable control, such that the spin speed of the inertia ring 37 can be regulated thereby to find and maintain resonance of the tubular resonator member 10.

The tubular resonator member 10, supported at its threaded section 16, typically at approximately twentyfive percent of its length from one of its ends, is subjected by the whirling inertia ring to a centrifugal force which is, in effect, a rotating radially oriented force vector. This .force vector is effective at the mid-section of the tubular member 10, and acts .to elastically bend or deform the tubing so that the central portion thereof moves bodily in a circular path (without bodily rotation on its axis), in the manner already described in the introductory part of this specification. Fig. 1a shows with exaggeration the tubular member 10 undergoing gyratory elastic motion characteristic of a standing wave for the fundamental resonant frequency of the tubular member for longitudinally propagated transverse elastic waves. The standing wave pattern for the tubular resonator member 10 is designated in a conventional way at st in FIG. 1, and has velocity antinodes V (regions of maximum vibration amplitude) at its mid-point and at each of its ends, and velocity nodes N (regions of minimized vibration amplitude) at points located approximately one-quarter of the length of the member 10 inwardly from each of its ends. It will be understood from known principles that such a standing wave as is diagrammatically represented at st in FIG. 1 results from the transmission along the length of the tubular member, from the vibration generator G, of laterally oriented (here gyratory) elastic deformation waves, which are reflected from the ends of the tubular member, and through interference with succeeding waves, produce the standing wave as represented. It should be clearly understood that tubular member 10 does not rotate bodily, but points on the member, including points on its forward end, describe circular paths in planes transverse of the longitudinal axis of the member. Such a circular path is represented by the circle 49in FIG. 4, the circle representing, of course with exaggeration, the path which will be described by the representative point 50 enclosed inside the circle 49. It might again be noted that such a gyratory standing wave performance is produced by a rotating radial force vector, which may be resolved into two component perpendicular transverse linear harmonic vibrations in quadrature. That is to say, if the mid-section of the tubular member 10 were subjected to an alternating force in the transverse plane along one direction line, and were simultaneously to be subjected to another alternating force in the same transverse plane but in a direction line at right angles to the first, with ninety degrees phase difference between the two, as by use of two synchronized alternating force generators phased ninety degrees apart, the resulting motion would be the gyration herein produced by the orbiting inertia ring 37. Such a substitution, which produces a resultant rotating force vector from two rectilinear generators, would be a clear equivalent.

As will appear, the two extremities of the tubular resonator member 10 describe circular paths or gyrations similar to those produced at the mid-section by the inertia ring 37. The tubular member 10 is virtually stationary at the nodal point N Where the jacket 19 and handle 46 are connected on. It is also virtually stationary where the stem 32 is coupled in, so as to avoid severe bending at the coupling point and thus early fatigue failure.

In operation, liquid is fed to the sprayer, preferably under pressure, via the hose 30, and fills the stem 32 and the duct 12 to the spray discharge orifice 13. Air under controlled pressure is simultaneously delivered to the air pressure chamber 43 via the hose 48 and the passageway 44. The air pressure so supplied is controlled so as to drive the inertia ring 37 at a number of gyrations per second which approximates the resonant frequency necessary to achieve the standin wave pattern illustrated in FIG. 1 and the performance rep-resented diagrammatically in FIG. la. This standing Wave performance is a condition of resonance in the tubular resonator member 10, at which peak amplitude of gyratory vibration is attained. The approach and attainment of resonance is readily perceived in practice, since vibrational amplitude rises rapidly as the peak resonant frequency is approached, and the sprayer settles down to high amplitude performance, with maximized flow volume from the discharge orifice 13 to atmosphere. The apparatus tend to lock in near but slightly under the peak of resonance, and then performs steadily at high output, largely irrespective of changes in extraneous conditions, such as in the volume of liquid supplied to the sprayers, its specific gravity, and the like. Furthermore, the sprayer, when once settle down to resonant vibratory operation, is characterized by a high Q performance, and is thereby stabilized against flow irregularities, variations in density or specific gravity of the liquid being sprayed, the casual occurrence of solids therein, and the like, all or any of which might otherwise tend to clog, deaden or stop the action. Moreover, at the outset, after non-use for a period of time, accumulations of previously used material on the interior of the sprayer are quickly cleaned out by the sonic vibration and normal performance established.

The spray from the discharge orific 13 consists of droplets in finely divided or atomized form, ejected with great force and velocity. This atomization and forcible ejection results from the high accelerations involved in the standing wave performance described in the foregoing. The gyratory activity of the nozzle portion of the apparatus, taking place at very high accelerations, at once atomizes the liquid and ejects it in multiple directions, so as to provide a desirable spray pattern, such for instance as represented at s in FIG. 1.

The atomizing and spraying action of the gyratory spray nozzle orifice end of the resonator on the ejected liquid can be appreciated best by considering that in the course of each gyration of the orifice, the liquid has been accelerated in all directions radially of the longitudinal resonator axis, and that the acceleration in each possible direction occurs at a frequency of, for example, a number of hundreds or thousands of times per second. Of course, the PHiQQ? 9f the. vibratory motion of the spray nozzle may be very small. The accelerations of the terminal region 13' of the liquid impelling and ejecting walls of the spray nozzle orifice, and the resulting lateral liquid atomizing and ejection forces acting perpendicularly thereto, however, are inherently exceedingly high.

A number of illustrative embodiments of the invention have now been described in considerable detail. It will be understood, however, that these are for illustrative purposes only, and various changes in design, structure and arrangement may be made without departing from the spirit and scope of the appended claims.

I claim:

1. A sonically vibratory liquid sprayer comprising:

an elongated resonator rod having a lateral mode of resonant standing wave vibration, with at least one velocity antinode at one end and at least one node space therefrom;

a vibration generator of an rbiting-mass type for applying a rotating radially oriented force to said resonator rod in a plane at right angles to said rod whereby said rod vibrates in a gyratory lateral standing wave pattern, said generator comprising a gyratory inertia ring encircling a portion of said rod in the region of a velocity antinode of said standing wave vibration, said portion of said rod having a closed continuous raceway therearound for said ring, said ring fitting said raceway with substantial clearance so as to be capable of a gyratory whirling action thereon;

fluid chest means mounted on said resonator rod for conveying fluid under pressure to said gyratory ring and including nozzle means for drivingly discharging said fluid against said ring; and

a spray nozzle at a velocity antinode end of said resonator rod, there being a liquid passageway through said rod having a discharge end communicating with said spray nozzle.

2. The subject matter of claim 1 wherein said fluid chest means is mounted on said resonator rod in the region of a node of said standing wave vibration.

3. The subject matter of claim 1 wherein said inertia ring raceway is provided at a velocity antinode of the standing wave vibration of said rod and said fluid chest means is mounted on said rod at a node of said standing wave vibration which is rearward of said antinode.

References Cited UNITED STATES PATENTS 2,960,314 11/1960 Bodine 239-102 3,039,699 6/1962 Allen 239-102 3,123,302 3/1964 Drayer 239-4 3,125,986 3/1964 Fortrnan et al. 239-102 3,145,931 8/1964 Cleall 239-102 3,178,115 4/1965 Drayer 239-102 EVERETT W. KIRBY, Primary Examiner. 

